SHORT TERM /TONIGHT THROUGH WEDNESDAY/
Satellite imagery shows stratus beginning to break up across the western Washington interior, while mostly clear skies prevail along the Pacific Coast and the Strait of Juan de Fuca. In the upper levels, a trough will push southward into California. A brief period of southerly winds aloft may promote some limited elevated instability over the Cascades, which will allow for convective showers to develop this afternoon into this evening. There is a low (10%) chance for a few isolated lightning strikes, but should be much fewer in coverage than what occurred yesterday. Elsewhere, clouds should continue to break up and scatter this afternoon, trending toward mostly clear skies tonight and the trough departs. Lows tonight will be in the mid 40s to low 50s.

Some patchy fog may develop Monday morning with mostly clear skies, but should evaporate in the morning. Split flow aloft with a weak ridge trying to nudge into the region will keep Monday dry. Partly cloudy skies will allow temperatures to warm into the upper 60s to low 70s. This is still a bit below normal, but it will be the warmest day of the week. High clouds will filter in Monday night as the next upper level trough and associated frontal system approaches the region on Tuesday.

Tuesday will be much cooler with highs in the 60s with widespread rain through much of the day. Rainfall amounts should remain light, a few tenths of an inch possible across the interior, with 0.5 to near 1 inch possible along the Pacific Coast and the windward Olympic mountains. Rain will devolve into showers Tuesday night into Wednesday before tapering off Wednesday evening.

LONG TERM /THURSDAY THROUGH SUNDAY/
The evolution of the long- term forecast remains uncertain as models struggle to converge on a solution. The trough will dip south in to California on Wednesday with a ridge centered over the east-central Pacific trying to build over the area. The ridge moves south, resulting in more zonal flow by the end of the week. For this weekend, ensemble cluster analysis shows about a 60% lean towards ridging for the weekend, with warmer and drier conditions, with 40% of model runs indicating additional troughs moving through for cooler and wetter conditions. The mean solution shows temperatures slowly climbing into the mid to upper 60s and a broad-brushed chance for showers from Friday into the weekend across western Washington.

LH

AVIATION
Mainly VFR with areas of MVFR in marine stratus lingering into the early afternoon. Clouds are favored to scour out this afternoon with mostly clear skies overnight. A weak marine push will bring in another round of low stratus and areas of patchy fog early Monday morning. Winds generally from the north 5-15 kt with onshore flow.

KSEA...MVFR with continued improvement to VFR this afternoon.
Another marine push early Monday morning may bring in MVFR ceilings (30% chance) with a low (15%) chance of IFR ceilings developing at the terminal. Surface winds generally light out of the north 5-10 kt easing overnight.

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MARINE
Generally benign conditions today as high pressure builds over the coastal waters. North to northwest winds across the waters today with gusts just below SCA over the far outer coastal waters and through the Strait of Georgia across the San Juan Islands northwestward. Building high pressure will generate a westerly push through the Strait of Juan de Fuca on Monday, though confidence is not high enough that it will reach SCA criteria. Low pressure will move southward across area waters on Tuesday with high pressure rebounding through the remainder of the week.

Seas 5 to 7 feet today through Tuesday, dropping to 4 to 5 feet Tuesday before rising again around 6 to 8 feet as a trough moves through mid-week. Seas will return to 4 to 5 feet by the end of the week as conditions calm.

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SEW WATCHES/WARNINGS/ADVISORIES
WA...None.
PZ...None.